#!/bin/sh -eu

passwd_hash=$(set -- $(md5sum /etc/passwd) && echo $1)
shadow_hash=$(set -- $(cat /etc/shadow | sed "s/:.*:0:99999:/:0:99999:/g" | md5sum) && echo $1)
group_length=$(cat /etc/group | wc -l)
gshadow_length=$(cat /etc/gshadow | wc -l)

passwd_orig_hash=$(set -- $(md5sum /etc/passwd.orig) && echo $1)
shadow_orig_hash=$(set -- $(cat /etc/shadow.orig | sed "s/:.*:0:99999:/:0:99999:/g" | md5sum) && echo $1)
group_orig_length=$(cat /etc/group.orig | wc -l)
gshadow_orig_length=$(cat /etc/gshadow.orig | wc -l)

if [ "$passwd_hash" != "$passwd_orig_hash" ]; then
    echo "/etc/passwd has changed during setup." >&2
    diff -Nrup /etc/passwd.orig /etc/passwd >&2
    exit 1
fi

if [ "$shadow_hash" != "$shadow_orig_hash" ]; then
    echo "/etc/shadow has changed during setup." >&2
    diff -Nrup /etc/shadow.orig /etc/shadow >&2
    exit 1
fi

if [ "$group_length" != "$group_orig_length" ]; then
    echo "/etc/group has changed during setup." >&2
    diff -Nrup /etc/group.orig /etc/group >&2
    exit 1
fi

if [ "$gshadow_length" != "$gshadow_orig_length" ]; then
    echo "/etc/gshadow has changed during setup." >&2
    diff -Nrup /etc/gshadow.orig /etc/gshadow >&2
    exit 1
fi

rm /etc/passwd.orig /etc/shadow.orig /etc/group.orig /etc/gshadow.orig